The work aims to prepare Cr2O3/TiO2 high temperature oxide ceramic composite coating on the surface of X70 pipeline steel by plasma spraying, and study the microstructure and electrochemical properties of the coating. Cr2O3/TiO2 high temperature oxide ceramic composite coating was deposited on the surface of X70 pipeline steel with wire-cut size of 40 mm×24 mm×6 mm by 9MC Plasma Control Unit plasma spraying system. Then, the microstructure and morphology of the coating were observed by metallographic microscope and scanning electron microscope, the phase composition of the coating was analyzed by X-ray diffractometer and the electrochemical corrosion performance of the coating was measured by electrochemical workstation. As a result, the Cr2O3/TiO2 high temperature oxide ceramic composite coating was composed of two phases: fully melted zone and semi-melted zone and showed typical plasma spraying coating structure and the bonding between the layers was close. There were Cr2O3-rich deposition areas and TiO2-rich deposition areas, but no phase transformation occurred. The fully melted liquid phase of TiO2 could be embedded in the gap of incompletely melted Cr2O3 structure to form solid solution structure. The self-corrosion potential of Cr2O3/TiO2 coating was between -0.4 ~ -0.3 V after test of electrochemical corrosion performance and higher than -0.6 ~ -0.5 V of X70 steel. The corrosion tendency was lagging behind, so the corrosion resistance was good. The plasma spraying parameters in this study are suitable, and the Cr2O3/TiO2 high temperature oxide ceramic composite coating which can improve the electrochemical corrosion resistance of X70 pipeline steel remarkably and has uniform structure distribution is prepared successfully.